Micrometer-caliper.



'UNITED STATES EDWARD s. SAVAGE, 0E ROCHESTER, NEW YORK.

MICEOMETEE-CALIPEE.

Specification of Letters Patent.

Patented Auf. 11, 1914.

Application mea May 19, 1913. serial No. 768,566.

To all whom t may concern.'

Vie it known that I, EDWARD S. SAVAGE, a citizen of the United States,and resident of Rochester, in the county ofMonroe and State of New York,have invented certain new and useful Improvements inMicrometer-Calipers, of which the following is a speciication. n

rlhis invention relates to calipers or measuring instruments in whichscrew-threaded rods or spindles are employed, as measuringdevices, inconnection with graduated means for indicating the degrees of movementofthe screw or spindle, and particularly to micrometer-calipers of thetype commonly described as direct-reading, wherein the incheating-meanscomprise a plurality of rotatable graduated members from whichdimensions may be read directly, as expressed by a series of decimalfigures.

@ne object of the invention is to produce a micrometer-caliper in whichlongitudinal movement is eliminated in the manuallyrotatable member orbarrel by which the micrometer-screw is actuated, and to this end 1employ a construction in which this barrel has only rotative movement,the relative longitudinal movement of the screw being permitted byproviding the barrel with a recess into and out of which the screw maybe moved longitudinally, and connecting the screw with the barrel by afeather and groove, or equivalent form of connection, to permit thebarrel to rotate the screw.

Another object of the invention is to produce an arrangement in whichthe indicating-mechanism is arranged and housed in a simple and compactmanner and Without substantially increasing the bulk of the instrument.To this end I inclose the gearccnnections between the several rotatableindicators, and between these indicators and the barrel, within aportion of the yoke, and retain them therein by a removable casing ashereinafter described and claimed.

A, third object of the invention is to provide simple and convenientmeans for takup wear between the micrometer-screw and the threadedmember or sleeve through which it moves, these means being particularlyadapted for use in connection with a caliper provided with thenovelrneans above referred to for actuating the screw.

Other objects and features of the invention will be set forth inconnection with the following description of the preferrred embodimentof the invention.l

'In the accompanying drawings z-Figure 1 .is a longitudinal section of aportion of a nncronfieter-caliper embodying the present invention,certain parts, including the micrometer-screw, being shown inside-elevation; Fig. 2 is a section on the line 2 3 in Fig" 1 lookingfrom left to right in the rlatter figure; Fig. 3 is a section on theline i 2-3, looking from right to left; Fig. d is a y side-elevation ofthe indicator-rings and the ;connecting-gears, in -their operative rela-Ition; Fig. 5 is a side-elevation, partly in longitudinal section, of acaliper embodying the inventionV in a modified form; Fig. 6 is 1asection on the line 6--7 in Fig. 5, looking from right to left in thelatter figure; Fig. 7 is a section on the line 6 7, looking from left toright; Fig. 8 is a section on the line 8-8 in Fig. 1, looking from rightto left in the latter figure, and showing only the parts immediatelyadjacent to the sec- `tion-plane; and Fig. 9 is a perspective-view` on alarger scale than the preceding figures, of one of vthe gear-members bywhich the in- :dicator-rings are connected.

`The novel arrangement of the barrel and ,the micrometer-screw is shownparticularly ,in Figs. 1 and 8, which illustrate the invention asembodied in a micrometer-caliper of which the general form is wellknown, the caliper having the usual yoke or frame 10, of which only aportion is illustrated. The micrometer-screw or spindle 11 is threadedinto a sleeve 12, which is seated in the yoke 10, and secured therein bya force-fit or in lany other convenient manner. The right- [handextremity 13 of the sleeve is slotted at several points, as shown inFig. 1, and is provided with a slightly tapered external thread embracedby a threaded ring 14. This ring is adapted te take up wear between thescrew `and the sleeve, by screwing the ring more or less along the part13 so as to contract this part against the screw.

The manually-operable member by which the screw is actuated is in theform of a barrel 15, which is journaled upon the sleeve 12, and isretained against longitudinal movement thereon by means hereinafterdescribed. This barrel is hollow, so that it may receive and inclose theright-hand end of the micrometer-screw, and it is provided with alongitudinal groove 16, which relceives a feather or lrey 17, this keybeing seated in a transverse slet in the screw and fixed therein bymeans of a pin 1S, as shown in Figs. 1 and 8. Owing to this arrangementrotation of the barrel causes corresponding rotation of the screw, andthis results in longitudinal movement of the screw through the sleeve12, while the screw moves more or less into the barrel, the rotativeconnection between the screw and the barrel being maintained by thefeather and groove just described. In this manner I avoid the use of alongitudinally-inovable barrel, and thus reduce the'liability to injuryor clogging of the mechanism which exists in calipers of the ordinaryconstruction, wherein the barrel or cap is simultaneously rotated Y andmoved longitudinally, 'about a closelyfitting inner cylindrical surfacewhich is more or lessrexposed in consequence of the longitudinalmovement of the barrel.

rEhe novel indicating-means, constituting a feature ot' the presentinvention, comprises threerings 20, 21, and 22, as shown in Figs. 1 to4, inclusive, these rings being journaled loosely upon the sleeve 12coaxial with the micrometer-screw and the barrel. rllhe indicator-ringsare inclosed by a generallycylindrical casing 28, which is seated, atits left-hand end, against a shoulder 2i on the barrel 12 and is securedin place by screws or any other convenient means. The. casing isprovided' also with a right-hand end-pon tion 25, which is perforated toreceive the barrel 15, and which extends o-ver and closes a part 26 ofthe yoke 110, which extends alongside the indicator-rings for a purposeto beV presently described. The ifirst indi cater-ring 20 is fixed tothe lett-hand end of the barrel 15 by means of a force-tit, or in anyother convenient manner, so that it turns with the barrel, and byengagement of its right-han`d end with the end-portion 25 of the casing23, the ring 2O prevents right-hand longitudinal movement of the barrel.The ring 20 is provided with decimal graduations, as shown in Fig. 4comprising two consecutive series of the digits 0 to 9, and themicrometer-screw is provided with 50 threads to the inch. Accordingly, acomplete rotation of the screw advances it through a space ofone-fiftieth of an inch, and at the same time the digits lon the ring20, by reference to a lixed point on the casing 23, indicate successiveone-thousandths of an inch in the longitudinal movement of the screw. Inorder that these digits may be visible for this purpose, the casing 23is provided Vwith sight-openings or windows 27, in

one side, as shown in Fig. 3, these openings being protected by a sleeve28 of mica or other transparent material, which iits within thercasingand is held in place by an inner sleeve 29 of thin sheet-metal, thesleeve 29 having perforations corresponding with the windows 27. Theposition of the screw is thus indicated by the digits which appearthrough the windows, and it will be understood that there are threewindows arranged in alineinent, and corresponding to the threeindicator-rings 20, 21 and 22. The second indicator-ring 21 is providedwith digits arranged in the same manner as those on the ring 20, andthese digits are adapted to indicate one-hundredth of an inch in themovement of the micrometer-screw, the gear-con` nectioiis between theindicator-rings being such as to cause the ring 21 to have a morementcorresponding to the space between two adjacent digits at the end ofeach half-rotation of the ring 20, the barrel 15, and themiorometenscrew.

rEhe actuating connections between the rings 2() and 21 comprise agear-member oi novel form, which is shown particularly in Fig. 9. Thismember is provided, at its ends, with pintles 30 and 31 by which it isrotatably supported, these pintles being journaled in bearing-blocks 32and retained in their bearings by engagement with the outer surfaces ofthe rings 2O and 21. The bearing-blocks 32 and the gear-member areinclosed within a longitudinal recess in the part 26 of' the yoke 10,this recess haring undercut portions, as shown in Fig. 3, to

receive corresponding projections on the bearing-blocks, and thus retainthem in opeiative position after they have been introducedlongitudinally in the recess. The gear-member, as shown in Fig. 9,comprises three operative sections, of which the first is provided withtwo oppositely-disposed gear-teeth 33 of peculiar ii'orm, while thesecond section comprises two similar gearteetli 3e extending at rightangles, or in staggered relation, to the teeth 33, and a. third sectioncomprises a pinion 85, oi: which the teeth may be of any convenient.torni and number. The teeth and 3l of the gear-member coperate with twoannular members which turn with the indicatorring 2O and which may beintegral therewith, as shown. rllie first of these members has a portion3G which is of the liull diameter of the ring, and which extends forslightly more than one-half ot' the circumference of the ring, the endsof the portion 36 being shown in dotted lines in Fig` 2. Beyond the endsof the portion 8G the ring is reduced iii diameter to form a recess 37of slightly less than oiie-halt the circuinlerence of the ring. rTheteeth 234i cooperate with the second annular member, which comprises aportion 3S orn the full diameter oit' the ring, this portion also beingot slightly more than one-half the cir-onintercnce, and being arrangedopposite to the portion 3G, as shown in Fig. 2, while in line with thisportion 38 there is a recess S9 cor responding in form, but opposite inlocation,

llO

to the recess 37. The pinion 35 engages an annular series of gear-teeth40 upon the indicator-ring 21.

1t will be apparent that in the position oi the parts illustrated in thedrawings, the two teeth 33 rest against the part 36 in such a mannerthat the gear-member is locked against rotation in either direction,while at the same time one of the teeth 34 projects into the recess 39.Accordingly, the indicator-ring 21 is locked, at this time, againstrotation, by the engagement between the gear-teeth 40 and the pinion 35.It the barrel 15 and the ring 20 be rotated in either direction,however, one end ot' the part 3S will come into engagement with one ofthe teeth 34, and at the same time the end of the recess 37 will reachone ot the teeth 33. By a continued rotation of the ring 20,accordingly, the part 38 may. cause a movement ot the gear-member, ot'the amplitude of one-fourth of a rotation, after which the position ofthe parts is reversed, the two teeth 34 being in locking engagement withthe part 38, while one of the teeth 33 projects into the recess 37.After this quarterrotation the gear-member is locked as before, but themovement of the gear-member causes a corresponding movement of theindicator-ring 21, equivalent to the space between two adjacent digitsthereon, thus bringing the next successive digit to view through one otthe windows 27, and this action may be repeated, the ring 21 being thusadvanced to the extent of two digits for each complete rotation of thering 20, corresponding to a movement of one-fittieth ot an inch on thepart of the micrometerscrew. The overlap between the corresponding parts3G and 38 on the indicator-ring 2O is equivalent, in form, to agear-tooth conforming to the space between the opposite surfaces of oneof the teeth 33 and the next adjacent tooth 34 on the gear-member, sothat the parts have the rotative operation of a pair of intermeshinggears, while at the same time, owing to the oifset position of theinterengaging parts, their action may be rendered intermittent, and theymay be caused to interlock with each other during the idle portions ofthe movement of the indicator-ring.

The operative connections between the indicator-rings 21 and 22 are ormay be in all respects similar to those between the rings 20 and 21, asillustrated in the drawings, and they need not, accordingly, bedescribed, it. being understood that each halfrotation of the ring 21results in a partial rotation of the ring 22, by which it is advancedthrough the space of one digit.

In the embodiment of the invention just described, the gear-teeth andthe operating surfaces on the indicator-rings are exterior, thegear-members being journaled alongside the indicator-rings. Anequivalent arrangement may be employed, however, in which the gear-teethand the operating-surfaces on the indicator-rings are internal, and inwhich the gear-members are journaled within the rings, and such anarrangement produces a mechanism in which a completely cylindrical outercasing may be employed, with no eccentric projections. Such anarrangement is illustrated in Figs. 5, G and 7. In this case themicrometer-screw 11 and the barrel may be substantially the `:same asthose previously described, and the threaded sleeve 42, through whichthe screw works, is fixed in the yoke 19 in the same manner as above,but no extension of the yoke is necessary to inclose the gear-memibers.1 gitudinal recess 43, as shown particularly in Fig. 6, which receivesthe teeth of the gear- {members, and also provides bearings for theirpintleS. rPhe casing 41 is completely cylindrical in form, and is ixedto the sleeve 42 and provided with windows, in the same The sleeve 42 isprovided with a lonmanner as in the construction above described. Thefirst indicator-ring 44 1s iixed with the recesses and projections onthe indicator-ring 2() in the iirst-described construction. Thegear-member connecting the `rings 44 and 45 has pint-les 48 and 49journaled in the recess 43, and retained therein by engagement with theinner surfaces of the ring 45 and th'e barrel 15, and it is providedalso with three sets of gear-teeth 49,

52 and 54, of which the iirst teeth 49 cooperate with the projection 50and the recess 51,the second set of teeth 52 coperate with theprojection 53 and the recess 63, and the third set of tee'th 54 coperatewith a series of teeth 55 on the ring 45, all in a manner equivalent tothat in which the parts coperate in the first-described construction.

The novel means for providing access to the adjusting-ring 14 may be thesame in both the above-described embodiments of the invention, and areshown particularly in Fig. 5. The ring 14 is provided with a series ofrecesses 60' adapted to receive a tool by which it may be turned. Thebarrel 15 is `provided with an opening 61 to afford access to theserecesses, and with an annular groove in which is seated a resilient.cleft ring 62. This ring may be turned within the groove so that itnormally covers the opening 61, thus excluding dust from this opening,and the ring is retained frictionally, owing to its resiliency, in theposition to which it has been turned. When the ring 14v is to be turnedto take up wear between the sleeve and the screw, the cleft ring 62 isturned to a. position in which the opening 6l is uncovered, owing to thespace between the ends of the ring. An instrument .with a fiat end, suchas an ordinary screwdriver, may then be introduced through the openingGl and inserted in one of the recesses 60., If the barrel be then turnedthe instrument and the ring 14 are correspondingly moved, so as to screwthe ring 14: upon the sleeve to the required degree.

Vhile the novel features of my invention abo-ve particularly set forthare preferably used in conjunction, it will be understood that theinvention is not limited to such conjoint use of these features, andthat it is not, in general, limited to the details of construction andarrangement of the embodiments of the invention herein described andillustrated in the accompanying dra-wings, but that the invention may beembodied in various other forms within its nature as defined in thefollowing claims.

l claim l. A micrometer-caliper having, in combination, a iixed sleeve;a micrometer-screw threaded therein; a barrel inclosing the end or' thescrew; connections, between the barrel and the screw, adapted to retainthem against relative rotation, but to permit relative longitudinalmovement; connections, between the inner end of the barrel and thesleeve, adapted to permit rotation of the barrel but retain it againstlongitudinal movement; and means for indicating the longitudinalmovement of the screw in accordance with the corresponding rotativemovement of the barrel.

2. A micrometer-caliper having, in combination, a fixed sleeve; amicrometer-screw threaded therein; a barrel inclosing the end of thescrew; connections, between the barrel and the screw, adapted to retainthem against relative rotation, but to permit relative longitudinalmovement; connections, between the inner end of the barrel and thesleeve, adapted to permit rotation of the barrel but retain it againstlongitudinal movement; and means for indicating the longitudinalmovement of the screw in accordance with the corresponding rotativemovement of the barrel, said means comprising graduated ringssurrounding the sleeve, and actuating-connections 'between the rings andthe barrel.

3. In a micrometer caliper, the combination, with a micrometer-screw,indicatingmeans actuated by the screw and comprising indicator-ringssurrounding the screw, and a yoke having a portion extending alongsidethe indicator-rings and provided with a recess opening toward the ringsand extending to the extremity of the yoke, of a series of gear-membersinterconnecting the rings and provided with integral oppositelyextending journals, and bearing-blocks cooperating with said journals,the gear-members and bearing-blocks being loosely mounted in said recessin the yoke and being removable and replaceable by endwise movementtherein.

4. A micrometer-caliper having, in combination, a micrometer-screw; alixed sleeve within which the screw is threaded, the sleeve having anexternally-threaded cleft end; an adjusting-ring screwed upon said. endof the sleeve and adapted to be rotated by the engagement therewith ofa. suitable instrument; a barrel inclosing the end of the screw andmanually rotatable to adjust the same, the barrel having an openingadjacent the adjusting-ring to permit access thereto; connectionsbetween the barrel and the screw adapted to permit relative longitudinalmovement but to cause the screw to rotate with the barrel; connections,between the sleeve and the barrel, adapted to permit the barrel torotate but to prevent longitudinal movement thereof; means, actu ated byrotation of the barrel, for indicating the longitudinal movement of thescrew, and means mounted on the barrel. and normally closing saidopening therein, but movable to uncover the opening to permit access tothe adjusting-ring.

5. A micrometer-caliper having, in combination, a sleeve; a yoke lixedto the sleeve and having a part extending alongside the sleeve andprovided with a longitudinal re cess having an open end directedoutwardly from the yoke; a micrometer-screw threaded in the sleeve;graduated indicator-rings surrounding the sleeve; a easing inclosing therings and provided with sight-openings and with a lateral opening toreceive the extending part of the yoke and a portion closing the end ofsaid recess therein; gear-members operatively connecting the rings andinclosed in said recess and retained therein by the casing; a barrelinclosing the end of the screw and rotatably mounted in the end of thecasing, the barrel being provided with means engaging the casing toprevent longitudinal movement of the barrel and with means operativelyconnecting it with the indicator mechanism; means for securing thecasing in place on the yoke; and connections, between the barrel and thescrew, adapted to permit relative longitudinal movement but to cause thescrew to be rotated by the barrel.

EDiVARD S. SAVAGE.

lVitnesses FARNUM F. Donsnv, D. GURNnn.

Copies of this patent may be obtained for ve cents each, by addressingthe Commissioner of Patents,

' Washington, D. C.

